semaphore.h

Go to the documentation of this file.

 
#ifndef CPPCOMMON_THREADS_SEMAPHORE_H
#define CPPCOMMON_THREADS_SEMAPHORE_H
 
#include "threads/locker.h"
#include "time/timestamp.h"
 
#include <memory>
 
namespace CppCommon {
 
 
class Semaphore
{
public:
 
    explicit Semaphore(int resources);
    Semaphore(const Semaphore&) = delete;
    Semaphore(Semaphore&& semaphore) = delete;
    ~Semaphore();
 
    Semaphore& operator=(const Semaphore&) = delete;
    Semaphore& operator=(Semaphore&& semaphore) = delete;
 
    int resources() const noexcept;
 
 
    bool TryLock();
 
 
    bool TryLockFor(const Timespan& timespan);
 
    bool TryLockUntil(const UtcTimestamp& timestamp)
    { return TryLockFor(timestamp - UtcTimestamp()); }
 
 
    void Lock();
 
 
    void Unlock();
 
private:
    class Impl;
 
    Impl& impl() noexcept { return reinterpret_cast<Impl&>(_storage); }
    const Impl& impl() const noexcept { return reinterpret_cast<Impl const&>(_storage); }
 
    static const size_t StorageSize = 40;
    static const size_t StorageAlign = 8;
    alignas(StorageAlign) std::byte _storage[StorageSize];
};
 
} // namespace CppCommon
 
#endif // CPPCOMMON_THREADS_SEMAPHORE_H